Fluid-pressure brake system.



W. H. SAUVAGB.

FLUID PRESSURE BRAKE SYSTEM.

APPLICATION FILED MAR.5,1909.

934,019. Patented Sept. 14.1909.

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a: u I 'W l l mi j m M g? 000 000 b3 2% b} w *1 EP NR R Inventor:

UNITED stra ns rArENT OFFICE.

WILLIAM H. ssuvaen, or NEW roux, N. Y.. ASSIGNOR or ONE-HALF 'ro arcnnnn r.

HAMILTON, 0F BALTIMORE, MARYLAND.

FLUID-PRESSURE BRAKE SYSTEM.

Specification of Letters Patent.

Patented Sept. 14, 1909.-

Application filed March 5, 1909. Serial No. 481,429.

To all whom it may concern:

Be it known that 1,, WILLIAM H. Sanvaon,

ence being had to the accompanying drawings, forming apart hereof.

his invention has for its general object to provide means for automatically restoring the predetermined ressure Which is intended to he maintains upon the brake pis tons throu h the operation of the usual retaini vefves during the descent of a long ado y a heavy train, whenever such pie etcrmined pressure is depleted through dancing M the retaining valves or leakage or from any other cause.

. In Letters Patent of the United States,

No. 902,115 granted October 27, 1908, there is set forth an invention which has the same oral purpose as that just mentioned, and It is the particular object of the resent invention to providea substitute or the in vention described in said Letters Patent which shall overcome some of the diflicclties which are more or lees necessarily incident to the ical use of the former invention, and particularly to provide means for the general purpose in view, the practical operation of which shall in no manner whatsoever interfere with or modify the action of the usual brake actuating devices. In the former invention, described in said Letters Patent, the automatic pressure regulating device was connected between the train ipe and the brake cylinder or the retaining valve pipe, an arrangement which led to the undeslrable results in practical operation above alluded to.

By the present invention the automatic pressure regulating device is connected between the auxiliary reservoir and the retaining valve :pipe 'so that a reduction in pressure in the retaining valve pipe immediately e'fiects a restoration of pressure in the retaining valve pipe and in the brake cylinder directl from the auxiliary reservoir, but on]. W en the retaining valve'is in operation. the retaining valve 18 not in operation and the pressure in the retaining valve pipe is exhausted, into the atmosphere, the automatic" pressure rting device is immediately thrown out of operation and the usual elements of the brake system then operate as if the automatic pressure regulating device did not exist and perform their usual functions without interruption or modification.

The invention will be more fully explained hereinafter with reference to the accompanying drawings in which it is illustrated and in which Fi ure 1 is a dia rammatic or outline view of so. much of an ordinary fluid 'pressure brake-system as is necessary to enable the application of the invention to be -understood, the automatic pressure restoring device being shown as directly connected between the auxiliary reservoir and the retaining valve pipe. Fig. 2 is a detail view, in section, of the automatic pressure restoring device on a larger scale than that of Fig. 1. Fig. 3 is a detail view, in section, of an ordinary retaining valve, such as may be employed in connection with the invention.

Except so far as the automatic pressure restoring device and its immediate connections are directly concerned, the brake system may beof any usual or suitable construction, as shown, for example, in Fig. 1 of the drawings, in which the train-pipe a,

supplied as usual with air under pressure from the locomotive and under the control o f the driver, is connected by a train ipe connection a with the triple valve (1 w lab is in turn connected with the brake cylinder 6 throu h the brake cylinder connection I) and wit the auxiliary reservoir 0, the lirake cylinder connection b being represented as passing through the auxiliary reservoir as usual. .The retainin'g va vs 6 is connected with the exhaust of the 'triple valve by the retaining valve pipe 0' and may comprise, as

"usual, a hand operated valve e which may sure in the retaining valve pipe under the control of the weighted valve e just before the train, of whic each car equipped with the retainin 5 summit of t e grade, so that during the descent of the grade a predetermined pressure shall be maintained in the retaining valve pipe and therefore, through the tri e valve and thebrake cylinder pipe I), in t e brake cylinder b, the brakes being thereby held set with a redetermined pressure during the descentv o the rade. The en near or drivePfinay, there ore, throw his va ve to the full release position, as is necessary to effeet the rechargin of the auxiliary reservoirs, without re edsing the brakes, and moreover, since the balance of braking power necessary to control the train, when the brakes are thus the operation of the brakes is in no wise afiected by theapplication of the resent invention, he can, by the application of straight air to the engine and tank brakes, maintain perfect control (if the train. The triple valve (1 may also be of ordinary construction, having a train pi e connect on ndicated at a a brake cylin GfCOIlIlGGtlOH ing and an exhaust and retainiilig valve connection indicated at 2, being ltse iary reservoir 0 and directly connected therewith.

The automatic pressure restoring device 1'" is directl connected on one side, as at f, to the auxi iary reservoir 0' and on the other side, as at to the exhaust or retaining valve pipe 0 and it is in this connection and co'mb'nation of the automatic restoringvalve that the present invention resides. T e construction of the valve may be of any suitable character which is adapted to control the communication between the auxiliar reservoir and the exhaust or retaining va ve pipe sure'in the exhaust or retainin valve pipe.

In the construction shown in ig. 2 whatever pressure is in the exhaust or retaining valve e is communicated through the ort and passa e h to a chamber h in whic is located su ject to the pressure in the pipe e,

a diap ragm or piston h, which is acted upon, in opposition to the fluid ressure in the chamber In. by a spring h w ich is ad- 55, justed so as to maintain in the chamber h the predetermined pressure which is to be maintained in thebrake cylinder. The stem h of the diaphragm or piston h carries a cam h which cooperates with the extension to g of a valve held by a spring 2 against its start in the wall of the valve 0 amber g, whichis in direct communication with the auxiliary reservoir 0 through the channel g. 130 long as the handle e of the retaining 66 vs vs is turned down so that the exhaust of valve is a part, passes over the.

set, lies in the'brakes on the engine and the tank, and since under the influence of the variation of presthe triple valve communicates directlywith the atmosphere, the piston or diap ragm h and therefore the cam h are held in their extreme forward positions. They thus remain and the device is therefore inoperative until the handle of the retaining valve is turned up so that the retaining valve shall operate to maintain in the brake cylinder the predetermined pressure under which the brakes are to be held. As soon as the retainingyalve becomes operative, the pressure' in the retaining valve pipe and,

through the triple valvfi the pressure in the brake cylinder, is imnie iately built up, until it reaches the predetermined pressure. Under the influence of this predetermined pressure in the pi e A, the dia hragm or piston k is thrust ack a ainst t e pressure 0 the spring! uickly over t e extension 9 of the valve g, t e piston h finally coming to rest against theend of the chamber in which it 15 located. If new the pressure in the pipe e, either through dancing of the retaining valve, or through leakage, or from any other cause, is depleted, the piston it yields to the pressure of the spring h and causes the cam to act against the extension 9 of the valve h and t e camh passes g, thrusting the valve slight] from its seat V and ermitting the fluid un er pressure in as usual, mounted upon one end of the auxilthe c amber g and in the auxiliary reservoir to enter the chamber h and its connections until the pressure in the pipe 0' and therefore in the brake cylinder, is restored to the predetermined degree. Inasmuch as the piston responds to sli ht variations of pressure, the pressure in t e brake cylinder and its connections can fall but slightly below the predetermined degree being immediately restored. When the necessity for maintaining the pressure in the brake cylinder is passed and the retaining valve handle is again turned down, the pressure in the pi e e will at once fall to atmospheric and t 0 piston b will be instantly thrown to its extreme forward position by the spring h". The cam it passes completely over the extension of the valve 9' so quickly that there is no material waste of pressure through the unseati'ng of the valve g.

I claim as my invention:

1. In a fluid ressure brake system, the combination wit a brake cylinder, an auxiliary reservoir, a triple valve, a retaining valve and a retaining valve connection, of means operated by reduction of pressure in the retaining valve connection to admit fluid under pressure from the auxiliary reservoir to the retaining valve connection.

2. In a fluid pressure brake system, the combination of a brake cylinder, an auxiliary reservoir, a triple valve connected with the brake cylinder and with the auxiliary reservoir, a retaining valve and a connection between the triple valve exhaust and the retaining valve, of means operated by reduction of pressure in the retaining valve connection to admit fluid under pressure from the auxiliary reservoir to the retaining valve connection.

it. In a fluid pressure brake system, the

combination of a brake cylinder, an auxiliar reservoir, a triple valve connected with the brake cylinder and with the auxil; iary reservoir, a retaining valve and a conneetion on the exhaust of the triple valve to the retaining valve, of a connection from the auxiliary reservoir to the retaining valve connection, a valve normally closing the last named connection and means operated by reduction of pressure in the retaining valve connection to open said last named valve.

4. In a fluid pressure brake system, the combination of a brake cylinder, an 'auxiliary reservoir, a triple valve connected with the brake cylinder and with the auxiliary reservoir, a retaining valve and a con-- nection on the exhaust of the triple valve to the retaining valve, of a direct connection froni the auxiliary reservoir to the retaining valve connection, a valve normally preventing the passage of fluid from the auxiliary reservoir to the retaining valve connection, a spring actuated piston subject to the pressure in the retaining valve connection and means actuated by the movement of the piston under reduction of pressure to open said valve.

5. In a fluid pressure brake system, the combination of a brake cylinder, an auxiliary reservoir, a triple valye connected with the brake cylinder and with the auxiliary reservoir, a retaining valve, a pipe connecting the exhaust of the triple valve With the retaining valve, :1 direct connection from the auxiliary reservoir to said pipe, a valve interposed in said connection and normally preventing the passage of fluid under pres sure from the auxiliary reservoir to the retaining valve pipe, and means operated by reduction of pressure in the retaining valve pipe to open said valve.

This specification signed and witnessed this 24th day of February, A. 1)., 1909.

WILLIAM H. sAUvAoE.

Signed in the presence of W. B. Gunning, AMBROSE L. OSHEA. 

